Method and apparatus of enabling multi band transmission

ABSTRACT

A method and apparatus for enabling multi-band transmission includes receiving a beacon on a first radio band and receiving the beacon on a second radio band. The beacon includes synchronization information for transmission on the first and second radio bands.

CROSS REFERENCE TO RELATED APPLICATIONS

This application is a continuation of U.S. application Ser. No.13/774,345, filed Feb. 22, 2013, which is a continuation of U.S.application Ser. No. 11/999,409, filed Dec. 4, 2007, which issued asU.S. Pat. No. 8,385,319 on Feb. 26, 2013, which claims the benefit ofU.S. Provisional Application No. 60/868,448, filed Dec. 4, 2006, whichare incorporated by reference as if fully set forth.

FIELD OF INVENTION

The present invention is related to wireless communication systems.

BACKGROUND

Ultra-wideband (UWB) technology is standardized under the ECMA 368/369specification. In particular, the ECMA 368/369 standard specifies adistributed medium access control (MAC) Layer and a physical (PHY) Layerfor WTRUs that support data rates up to 480 megabits per second (Mbps).The PHY layer is designed to operate in the 3.1 to 10.6 gigahertz (GHz)frequency spectrum and has been accepted as a common platform fortechnologies such as next generation Bluetooth®, wireless universalserial bus (WUSB) and wireless Firewire (IEEE 1394).

The ECMA 368 PHY uses a multi-band orthogonal frequency divisionmodulation (MB OFDM) to transmit information. The ECMA 368 PHYspecification operating frequency spectrum is divided into 5 radio bandgroups with each radio band, or equivalent carrier spacing, being 528MHz. The first four radio band groups have three radio bands of 528 MHz,while the fifth band group includes two radio bands of 528 MHz each. Thecapability to operate in the first radio band group is mandatory.However, operating in the other radio band groups is optional.

The ECMA 386 MAC layer has a completely distributed architecture andprovides MAC services to a higher layer protocols or to an adaptationlayer. There is no central coordinating device and each device supportsall MAC functions. Devices within radio range coordinate with each otherusing periodic beacon frames. These beacon frames provide networktiming, scheduling and capability information, as well as otherinformation and functions.

One way in which the beacon frames provide information is via aninformation element (IE) included in the beacon frame or in a commandframe. This IE may include a beacon period (BP) switch IE and/or adistributed reservation protocol (DRP) IE. The BP switch IE, inparticular, may include an element ID field, a length field, a BP movecountdown field, a beacon slot offset field, and a BP start (BPST)offset field.

In addition, MAC superframe structures from ECMA 368 include beaconperiods (BPs) and medium access slots (MASS).

One issue with the mechanism and rates currently supported by the ECMA368/369 standards is that it may be inadequate to support applicationssuch as high definition TV (HDTV) which requires a data rate of 1 Gbpsor greater, depending on the HDTV format. It would therefore bebeneficial to provide a method and apparatus to enable multi-bandtransmission that can enable higher data rates in next generation (NG)UWB.

SUMMARY

A method and apparatus for enabling multi-band transmission isdisclosed. The method includes transmitting a beacon on a first radioband and transmitting the beacon on a second radio band. The beaconincludes coordination information for transmission on the first andsecond radio bands.

BRIEF DESCRIPTION OF THE DRAWINGS

A more detailed understanding may be had from the following description,given by way of example and to be understood in conjunction with theaccompanying drawings wherein:

FIG. 1 shows an example of a distributed wireless communication systemincluding a plurality of WTRUs in communication with one another;

FIG. 2 is a functional block diagram of a WTRU of FIG. 1;

FIG. 3 is a flow diagram of a method of enabling multi-bandtransmission; and

FIG. 4 is a flow diagram of an alternative method of enabling multi-bandtransmission.

DETAILED DESCRIPTION

When referred to hereafter, the terminology “wireless transmit/receiveunit (WTRU)” includes but is not limited to a user equipment (UE), amobile station, a fixed or mobile subscriber unit, a pager, a cellulartelephone, a personal digital assistant (PDA), a computer, or any othertype of user device capable of operating in a wireless environment. Whenreferred to hereafter, the terminology “base station” includes but isnot limited to a Node-B, a site controller, an access point (AP), or anyother type of interfacing device capable of operating in a wirelessenvironment.

FIG. 1 shows an example of a distributed wireless communication system100 including a plurality of WTRUs 110. As shown in FIG. 1, the WTRUs110 are all in communication with one another. However, although threeWTRUs 110 are shown in communication with one another, it should benoted that any number of WTRUs 110 may be included in the distributedwireless communication system 100 and every WTRU 110 may or may not bein communication with every other WTRU 110.

FIG. 2 is a functional block diagram of a WTRU 110. In addition to thecomponents that may be found in a typical WTRU, the WTRU 910 includes aprocessor 115, a receiver 116, a transmitter 117, and an antenna 118.The processor 115 is configured to enable multi-band transmission, asdescribed by way of example in more detail below. The receiver 116 andthe transmitter 117 are in communication with the processor 115. Theantenna 118 is in communication with both the receiver 116 and thetransmitter 117 to facilitate the transmission and reception of wirelessdata. Although only one transmitter, receiver and antenna are depictedin the WTRU 110 as shown in FIG. 2, the WTRU 110 may include a pluralityof transmitters, receivers and antennas.

FIG. 3 is a flow diagram of a method 300 of enabling multi-bandtransmission. Implementation of the method 300 provides and increaseddata rate for WTRUs implementing NG UWB technology. Additionally,bandwidth may be expanded by utilizing more than one radio band, whichis currently 528 MHz.

In step 310, the WTRU 110 transmits a beacon on more than one radioband. The beacon includes information relating to coordination oftransmission with the WTRU 110 on more than one radio bands. Thetransmission may occur on adjacent radio bands or non-adjacent radiobands, and the radio bands may include a single radio or dual-radiooption.

The WTRU 110 coordinates, or synchronizes, beacons across all of theradio bands (step 320). This synchronization may include aligning beaconperiod (BP) start times for different beacons across bands.Alternatively, the WTRU 110 may have knowledge of the relative offsetsamong the BP start times in the different bands. Because a BP expandsfor longer than the beacon transmission duration, partial timeoverlapping of BPs can occur. Additionally, non-overlapping beacontransmissions can be achieved.

If the WTRU 110 includes a single radio transmitter, the WTRU 110transmits on more than one radio band to increase the data rate. Forexample, the WTRU 110 will transmit on adjacent radio bands. In thiscase, the WTRU 110 synchronizes (step 1020) the beacon by aligning thebeacon period start time in all radio bands of an expanded bandwidthtransmission (EBT).

In another scenario, the WTRU 110 may transmit on a first radio band,then switch, or “hop,” to a second radio band where the WTRU 110monitors for the beacon in the BP and transmits on the second radioband. An example of this scenario may include where the WTRU 110including a single radio utilizes resources on multiple bands, such ashalf of the medium access slots (MASS) on one radio band and half onanother. In this case, the BPs on different bands may not be aligned,but may have a known offset. The WTRU 110 in this scenario utilizes bothbeacons at different points in time. This scenario may also facilitatereserving resources via DRP on multiple bands using one beacon, such asa master beacon.

Alternatively, the WTRU 110 may have EBT utilized in the non-beaconperiod, (i.e., non-BP), only. For example, the WTRU 110 may utilize asingle radio transmitter that transmits simultaneously on two adjacentbands with single radio band transmissions occurring during the BP. Thiswill enable proper reception of the beacon transmissions.

In another scenario, the WTRU 110 may include more than one radiotransmitter. FIG. 4 is a flow diagram of an alternative method 400 ofenabling multi-band transmission. As depicted in the method 400, theWTRU 110 includes a plurality of radio transmitters.

In step 410, separate radios, or radio transmitters, of the WTRU 110transmit independently on separate radio bands. For example, a firstradio may transmit on one radio band while a second radio transmits on asecond radio band. In this case, there may be no need for BPsynchronization or alignment, since the two beacons are transmitted overseparate radio bands and do not conflict with one another.

The WTRU 110 monitors the transmission medium (step 420) for theexistence of a beacon frame (step 430). If no beacon frames exist (step430), then the WTRU 110 creates a BP (step 440). In particular, a BPstart time alignment in all bands of an EBT is utilized so thereservations of an EBT for the WTRU 110 in all bands are aligned. Onescenario in which this may be achieved is to reuse the BP switch IE tosynchronize BPs across all radio bands.

The WTRU 110 coordinates the beacon synchronization across all the bands(step 450). In one example, a WTRU 110 equipped for EBT transmits abeacon frame in a given radio band according to its own BP (step 460).Other WTRUs that receive this beacon frame align their BPs with a BPswitch IE. For example, before switching to the new BP, the WTRU 110 maytransmit a beacon on its previous BP where the BP switch IE is added toindicate the move to the new BP. The EBT equipped WTRU 110 may transmitsimultaneously in all radio bands, or in sequence from radio band toradio band. Accordingly, the result is that the BPs in all bands arealigned to the BP of the EBT WTRU 110. This may require multiplesuperframes to perform in this manner.

Alternatively, the WTRU 110 may introduce a new EBT BP switch IE to theother WTRUs in the system that instructs them to synchronize their BPsto the value specified at a time specified in the EBT BP switch IE.Accordingly, the new EBT switch IE includes, in a field, a new beaconperiod timing and a time to change the BP. Additionally, the WTRU 110may provide EBT capabilities, such as default channels and defaultexpanded channels in the beacon transmitted.

Although features and elements are described above in particularcombinations, each feature or element can be used alone without theother features and elements or in various combinations with or withoutother features and elements. The methods or flow charts provided hereinmay be implemented in a computer program, software, or firmware tangiblyembodied in a computer-readable storage medium for execution by ageneral purpose computer or a processor. Examples of computer-readablestorage mediums include a read only memory (ROM), a random access memory(RAM), a register, cache memory, semiconductor memory devices, magneticmedia such as internal hard disks and removable disks, magneto-opticalmedia, and optical media such as CD-ROM disks, and digital versatiledisks (DVDs).

Suitable processors include, by way of example, a general purposeprocessor, a special purpose processor, a conventional processor, adigital signal processor (DSP), a plurality of microprocessors, one ormore microprocessors in association with a DSP core, a controller, amicrocontroller, Application Specific Integrated Circuits (ASICs), FieldProgrammable Gate Arrays (FPGAs) circuits, any other type of integratedcircuit (IC), and/or a state machine.

A processor in association with software may be used to implement aradio frequency transceiver for use in a wireless transmit receive unit(WTRU), user equipment (UE), terminal, base station, radio networkcontroller (RNC), or any host computer. The WTRU may be used inconjunction with modules, implemented in hardware and/or software, suchas a camera, a video camera module, a videophone, a speakerphone, avibration device, a speaker, a microphone, a television transceiver, ahands free headset, a keyboard, a Bluetooth® module, a frequencymodulated (FM) radio unit, a liquid crystal display (LCD) display unit,an organic light-emitting diode (OLED) display unit, a digital musicplayer, a media player, a video game player module, an Internet browser,and/or any wireless local area network (WLAN) or Ultra Wide Band (UWB)module.

What is claimed is:
 1. A method implemented in a first wirelesstransmit/receive unit (WTRU) for multi-band communication with a secondWTRU, the method comprising: receiving, from the second WTRU, a firstbeacon frame by a first receiver on a first radio band, wherein thefirst beacon frame includes an indication that the second WTRU iscapable of transmitting on more than one radio band, and wherein thefirst beacon frame includes synchronization information that enables thefirst WTRU to locate a second beacon frame on a second radio band; andreceiving, from the second WTRU, the second beacon frame by a secondreceiver on the second radio band in accordance with the synchronizationinformation included in the first beacon frame.
 2. The method of claim1, wherein the synchronization information is included in a beaconperiod (BP) switch information element (IE).
 3. The method of claim 1,wherein at least one of the first and second beacon frames includes anexpanded bandwidth transmission (EBT) BP switch IE, wherein the EBT BPswitch IE includes a field indicating a new beacon timing value and atime to change to a new BP.
 4. The method of claim 1, wherein the firstand second beacon frames are received simultaneously on the first andsecond radio bands.
 5. The method of claim 1, wherein the first andsecond beacon frames are received sequentially on the first and secondradio bands.
 6. The method of claim 1, wherein at least one of the firstand second beacon frames includes EBT capabilities of the second WTRU.7. The method of claim 6, wherein the EBT capabilities include any oneof the following: a default channel and a default expanded channel.
 8. Afirst wireless transmit/receive unit (WTRU) in communication with asecond WTRU, the first WTRU comprising: a first receiver configured toreceive, from the second WTRU, a first beacon frame on a first radioband, wherein the first beacon frame includes an indication that thesecond WTRU is capable of transmitting on more than one radio band, andwherein the first beacon frame includes synchronization information thatenables the first WTRU to locate a second beacon frame on a second radioband; and a second receiver configured to receive, from the second WTRU,the second beacon frame on the second radio band in accordance with thesynchronization information included in the first beacon frame.
 9. Thefirst WTRU of claim 8, wherein the synchronization information isincluded in a beacon period (BP) switch information element (IE). 10.The first WTRU of claim 8, wherein at least one of the first and secondbeacon frames includes an expanded bandwidth transmission (EBT) BPswitch IE, wherein the EBT BP switch IE includes a field indicating anew beacon timing value and a time to change to a new BP.
 11. The firstWTRU of claim 8, wherein the first receiver and the second receiver arefurther configured to receive the first and second beacon framessimultaneously on the first and second radio bands.
 12. The first WTRUof claim 8, wherein the first receiver and the second receiver arefurther configured to receive the first and second beacon framessequentially on the first and second radio bands.
 13. The first WTRU ofclaim 8, wherein at least one of the first and second beacon framesincludes EBT capabilities of the second WTRU.
 14. The first WTRU ofclaim 13, wherein the EBT capabilities include any one of the following:a default channel and a default expanded channel.